Many therapeutic agents cannot be delivered effectively to treat cancerous cells by conventional means such as ingestion, injection, inhalation, and topical application because many of these agents are subject to rapid degradation. Further, direct systemic administration of many therapeutic agents often causes detrimental side-effects. For example, those agents that target actively dividing cells are not able to discriminate between actively dividing cancer cells and actively dividing healthy cells. Thus, in the process of destroying or inhibiting the rapidly dividing cancer cells, many of the healthy cells are also damaged.
Accordingly, there is an unmet need for targeting of solid tumor cells for the treatment of malignant diseases that will show an affinity for cancer cells, deliver therapeutic payloads that inhibit proliferation and/or destroy cancerous tumor cells without inhibiting and/or destroying normal cells.